Ti3C2 nanosheets modified Zr-MOFs with Schottky junction for boosting photocatalytic HER performance.

Here, we present a novel TU series based on Ti 3 C 2 nanosheets modified UiO-66-NH 2 with Schottky junction for photocatalytic H 2 evolution. • Ti 3 C 2 nanosheets were integrated with UiO-66-NH 2 for enhanced photocatalytic HER activity. • TU series displayed superior photocatalytic H 2 evolution activity and stability. • Spatial separation and transfer of charge carriers was realized by the Schottky junction. • Ti 3 C 2 nanosheets with functional groups possessed abundant active sites. • DFT calculations revealed O-TC possessed the most positive Fermi level and lowest ΔG H*. As newly-developing non-noble metallic co-catalysts, MXenes have attracted intensive attention as an ideal candidate to promote the photocatalytic H 2 -production activity. In this study, Ti 3 C 2 nanosheets prepared by intercalation were further attached to porous MOFs (UiO-66-NH 2) via one-pot hydrothermal method to form face-to-face intimate contact. The obtained TU10 presented the highest photocatalytic H 2 -evolution rates in TU series, exceeding that of pure UiO-66-NH 2 by approximately 8 times. The speculation revolving about enhanced photocatalytic H 2 -production performance was proposed as the presence of exposed active sites at the edge of Ti 3 C 2 nanosheets and spatial separation and transfer of charge carriers introduced by the Schottky junction at TU series interface, which accumulated the photo-induced electrons on the surface of Ti 3 C 2 nanosheets and improved its electron-donating ability. The DFT calculations revealed that O-terminated Ti 3 C 2 possessed the most positive Fermi level and the lowest Gibbs free energy (|ΔG H* | = 0.08 ≈ 0). This work may provide new insights for constructing MXenes/MOFs structure based on Schottky junction effect to achieve high photocatalytic H 2 -production performance. [ABSTRACT FROM AUTHOR]